Looping tower carriage suspension



LOOPING TOWER CARRIAGE SUSPENSION Filed Sept. 16, 1966 6 Sheets-Sheet l TEE-.1-

s I I 1 i i i l I J INVENTOR. WILLIAM A. TURNER. B 0 fl:

Attorney June 4, 1968 w. A. TURNER 3,386,638

LOOPING TOWER CARRIAGE SUSPENSION Filed Sept. 16, 1966 3 Sheets-Sheet 2 l/VVEN TOR. WILLIAM A. TURNER M w w Attorney June 4, 1968 w. A. TURNER 3,386,638

IN VE/V TOR. WILLIAM A.

TURNER f forney United States Patent 3,386,638 LOOPING TOWER CARRIAGE SUSPENSION William A. Turner, Yardley, Pa., assignor to United States Steel Corporation, a corporation of Delaware Filed Sept. 16, 1966, Ser. No. 579,987 2 Claims. (Cl. 226-119) The present invention relates generally to looping towers for accumulating strip and strip-like material and, more particularly, to an improved cable suspension arrangement for the movable carriage of a looping tower.

As is well knOWn, a continuous strip processing line requires means for accumulating or gathering strip where it is necessary to accumulate strip at a point in the processing line ahead of the processing elements thereof so that the line can continue in operation when coils of strip are being fastened end-to-end and when the strip is being sheared and removed at the opposite end of the line. An apparatus commonly used as a mechanical accumulator for strip is a looping tower which consists of a vertically disposed framework supporting two horizontal banks of rolls through which the strip is threaded, with one set of rolls mounted in a fixed location in the tower and the other set mounted on a carriage vertically movable within the tower.

The vertically movable carriage is usually supported by counterweights attached to its four corners to counterbalance the carriage deadwei'ght. The tower framework includes vertical guide rails or posts which extend along each side of the path of the carriage and on which the carriage is slidably disposed so as to be guided in its movement vertically within the tower. A dual cable rope drive is connected to the carriage to move it vertically in the tower. The carriage is raised and lowered in the tower to maintain the strip at a desired uniform tension as it travels from the entry side to the exit side of the tower.

Prior to my invention, the ropes or cables making up the dual rope drive for moving the carriage were attached to the ends of a pair of rope-support arms pivotally mounted on the carriage. The support arms extended between and were pivotally mounted between a pair of rigid vertical plates which were suspended from the carriage framework. The two support arms were spaced one above the other and each was pivoted intermediate its ends on a separate pivot pin which extended between the pair of vertical plates. The two ropes effective to raise the carriage were attached by one end to one extremity of one support arm and the other to the opposite extremity of the same support arm. Each of the raising ropes extended from its respective support arm, around pulleys disposed in the upper portion of the tower and then to wrap-around connection on two reversible driven drums located adjacent the bottom of the tower. The two ropes of the rope drive which functioned to lower the carriage were each attached by one end to opposite ends of the other support bar and extended therefrom to wrap-around connection with the drums on the ends thereof opposite to those around which the raising ropes were Wrapped. The lowering ropes were wrapped around the drums in a direction opposite to that in which the raising ropes were wrapped so that the carriage was raised when the drums were driven in one direction and was lowered when the drums were driven in the opposite direction.

The strip in process in a continuous processing line constantly weaves as it passes from the entry side to the exit side of the tower, and whenever the strip centerline is eccentric to the carriage centerline, transverse tilting of the carriage results. Such tilting of the carriage prior to my invention caused the rigidly fastened pair of bar-supporting plates to also tilt which moved the pivot points of the rope-support bars unequal distances from the carriage centerline. This created unequal tensions in the drive ropes and caused them to move eccentrically to the carriage centerline so that the ropes would often become twisted and/ or excessively slackened. Such conditions resulted in frequent rope failure and undesirable displacement of the ropes from the proper peripheral grooves of the drive drums.

It is, accordingly, the primary object of my invention to provide an improved drive rope suspension arrangement for the movable carriage of a looping tower wherein :a pair of rope-support arms is mounted on the carriage on a common pivot shaft for independent pivotal movement transversely of the centerline of the horizontal path of travel of strip through the tower whereby the drive ropes move equal distances eccentric to the carriage centerline as the strip weaves from side to side.

This and other objects will become more apparent from the following specification and attached drawings in which:

FIGURE 1 is an elevational view partly in section of a looping tower having the cable suspension arrangement of the invention incorporated therein;

FIGURE 2 is an enlarged vertical sectional view taken along the line II--II of FIGURE 1;

FIGURE 3 is a cross-sectional view taken along line III-III of FIGURE 2;

FIGURE 4 is a vertical sectional view taken along the line IV-IV of FIGURE 1;

FIGURE 5 is a schematic illustration in perspective of the cable suspension arrangement of the movable carriage; and

FIGURE 6 is a perspective view of the rope-supporting arms of the invention.

Referring more particularly to the drawing, reference character 2 designates a looping tower for accumulating strip S, having a bank of rolls 4 mounted in a fixed horizontal framework adjacent the top of the tower and a bank of rolls 6 mounted on a counterweighted carriage framework 8 which, in turn, is mounted for vertical movement in the tower toward and away from the fixed [bank of rolls 4' along a pair of guide posts 10 by means of guide rollers 12. An example of a carriage guide arrangement of this type is described and shown in copending application Ser. No. 580,100, filed Sept. 16, 1966. Strip S is trained around the rolls 4 and 6 which cooperate to loop and accumulate the strip advancing through the tower. Suitable driven feed rolls and pull-out rolls (not shown) are provided adjacent the entry and exit sides, respectively, of the tower for advancing the strip.

A dual rope drive, designated generally by reference numeral 14, is attached to the carriage framework 8 for raising and lowering the same. The dual rope drive includes a pair of ropes 16 for raising the carriage and a pair of ropes 18 for lowering the carriage. The ropes 16 and 18 are driven in conventional manner by a pair of powered drums 20 mounted on a common shaft.

The carriage is raised and lowered in the tower to maintain a uniform desired tension in the strip traveling through the tower or being accumulated therein.

The apparatus thus far described is not claimed as my invention, the details of which will now be set forth.

A pair of spaced channel members 21 is welded to and extends transversely of the carriage 8. A pivot shaft 22 is connected with and extends between the two channel members 21 for pivotally supporting a first ropesupporting frame 24 and a second rope supporting frame 26, which is nested within the frame 24. One end of each of the ropes 16 is attached to Opposite ends of the frame 24 and extends therefrom around a pair of pulleys 28 journaled in the top of the tower. The ropes 16 are trained around their respective pulleys 28 and from there extend to drums 20. One end of the ropes 18 is attached to opposite ends of the frame 26 and extend therefrom to the drums 20. The ropes 16 are wrapped in one direction around one end of each of the drums 20 while the ropes 18 are Wrapped around the other ends of the drums 20 in the opposite direction so that raising or lowering of the carriage is effected by rotating the drums.

A sleeve 30 around which frame 24 pivots is provided around the pivot shaft 22. The frame 26 is formed with an integral hub 32 which pivots about the sleeve 30.

Through the use of the suspension arrangement of my invention wherein the two rope supporting frames 24 and 26 are mounted on a common pivot shaft, lateral movement of the pivot point of the rope supporting frame is minimized. As the strip S weaves from side to side as it advances through the tower, pivot shaft 22 will move only a slight distance off center and the dual drive ropes 16 and 18 are moved an equal distance eccentric to the carriage centerline. This reduces the possibility of excessively slackened or twisted rope. The support arrangement of the invention also minimizes premature rope failme, and carriage failure due to the drive ropes jumping out of the peripheral grooves of drums 20, as well as eliminating a cause of strip breakage.

It will be noted that the pivot shaft 22 extends centrally of the carriage framework 8 and is aligned with the horizontal centerline of the path of the strip advancing through the tower.

Although I have shown but one embodiment of my invention it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

I claim:

1. In a looping tower for accumulating strip, including a frame fixed to the tower, and a frame reciprocable toward and from the fixed frame, said frames having rolls journaled therein around which strip is trained, a pair of ropes for raising said reciprocable frame and a pair of ropes for lowering it, and beams carried by said reciprocable frame and pivoted thereto, to the ends of which said pairs of ropes, respectively, are secured, wherein the improvement comprises a single pivot shaft normal to said reciprocable frame, on which both beams are journaled.

2. Apparatus as defined by claim 1 in which said pivot shaft is aligned with the horizontal centerline of the path of strip trained around said rolls.

References Cited UNITED STATES PATENTS 3,109,572 11/1963 Herr 226119 EDWARD A. SROKA, Primary Examiner. 

1. IN A LOOPING TOWER FOR ACCUMULATING STRIP, INCLUDING A FRAME FIXED TO THE TOWER, AND A FRAME RECIPROCABLE TOWARD AND FROM THE FIXED FRAME, SAID FRAMES HAVING ROLLS JOURNALED THEREIN AROUND WHICH STRIP IS TRAINED, A PAIR OF ROPES FOR RAISING SAID RECIPROCABLE FRAME AND A PAIR OF ROPES FOR LOWERING IT, AND BEAMS CARRIED BY SAID RECIPROCABLE FRAME AND PIVOTED THERETO, TO THE ENDS OF WHICH SAID PAIRS OF ROPES, RESPECTIVELY, ARE SECURED, WHEREIN THE IMPROVEMENT COMPRISES A SINGLE PIVOT SHAFT NORMAL TO SAID RECIPROCABLE FRAME, ON WHICH BOTH BEAMS ARE JOURNALED. 